WAVES and MODES a room resonance calculator This is a Microsoft Excel program for the PC that calculates the resonance frequencies for rectangular rooms, and that shows graphically the sound pressure distributions along the major axes of the room.

WAVES and MODES a room resonance calculator This is a Microsoft Excel program for the PC that calculates the resonance frequencies for rectangular rooms, and that shows graphically the sound pressure distributions along the major axes of the room. To use it, type your room dimensions into the WAVES component of the calculator. The dimensions are automatically entered into MODES. Its use is explained in Part 3 of "Loudspeakers and Rooms for Multichannel Audio Reproduction". http://www.harman.com/wp/pdf/Room%20Mod ... or2002.xls

Excel calculation file: Jeff D. Szymanski - Room Modes is a spreadsheet from Jeff D. Szymanski that calculates normal room modes for rectangular spaces. Detailed instructions are included on the first sheet. A Bonello distribution curve is included with information on how to interpret the results. http://www.studiotips.com/tools/MODESv2p.zip

A timber slat type Helmholtz resonator (Walls Ceiling) can be an elegant way to create absorption. However take into account, that narrow ban absorption can also be a disadvantage. Broadbanded absorption is the general rule. http://www.saecollege.de/reference_mate ... mholtz.xls

On-Line calculation tools Several on line calculation tools are available (often in Java script).

Acoustics Software on-line The software on the links below is provided without any guarantee whatsoever. A recent browser will be required to run Java or JavaScript programs. The software can also be saved and run offline. http://www.measure.demon.co.uk/software.html

TROX Technik This is probably the only gasflow (ventilation) attenuator program on the net. This program allows to calculate the attentuation of splitter and circular attenuators (disadvantage, it's based on standard Trox products, advantage the used absorption material is mineral wool, so the results can be used).) http://www2.troxtechnik.de/auslegung/sd ... anguage=GB

References to calculate other tuned Helmholtz resonators This are not calculation files, but files explaining how to calculate other than slatt type Helmholtz resonators.

IPA Acoustics Handbook: How to use perforated steel sheet This is a VERY GOOD publication of the Industrial Perforators Association (IPA), related to the use of perforted steel sheets, as wel for broadband absorption as well for tuned resonators. http://www.iperf.org/ac00.htm

Different Calculation Tools on the StudioTips site itself Several calculation tools originating from list members collected on the studiotips.com site. As well for MAC as well for PC. http://www.studiotips.com/tools

Logs, Bels, Decibels, Adding & Subtracting Decibels Not used to work with decibels? How to add or subtract them. Follow the instructions on this link and it will have no secrets for you anymore. http://www.steve-o.com/public/unc/decibel/